Gof Patterns Overview

GOF(Gang Of Four) patterns are commonly used reusable object oriented programming patterns while developing highly maintainable and reusable software.

GOF patterns can be categorized into creational patterns, structural patterns and behavioral patterns. Most of the patterns follow object-oriented principles and SOLID principles.

Creational Patterns #

Creational patterns deal with object creation. Frequently used creational patterns are

• Singleton Pattern

• Prototype Pattern

• Simple Factory Pattern

• Factory Method Pattern

• Abstract Factory Pattern

• Builder Pattern

• Object Pool Pattern

Structural Patterns #

Structural patterns deal with complex structures creation by making use of relations between objects and classes. Many structural patterns are based on Inheritance and Polymorphism. Most commonly used structural patterns are

• Adapter Pattern

• Proxy Pattern

• Bridge Pattern

• Decorator Pattern

• Composite Pattern

• Facade Pattern

• Flyweight Pattern

There are other structural patterns but not commonly discussed with GOF pattern. Following are few

• Marker Interface

• Module

Marker Interface #

Marker interface is an empty interface to mark specific classes (such as Cloneable and Serializable). Marker interface makes search by interface possible.

Module #

In software development classes are grouped together to implement an application feature or concept to form a module. Modular architecture contains multiple patterns like MVC, MVVM, etc.

Behavioral Patterns #

Behavioral patterns deal with object interaction, communication and control flows. Most behavioral patterns are based on composition and delegation rather than inheritance. Frequently used behavioral design patterns are

• Chain of Responsibility Pattern

• Command Pattern

• Interpreter Pattern

• Iterator Pattern

• Observer Pattern

• Mediator Pattern

• Memento Pattern

• State Pattern

• Strategy Pattern

• Template Method Pattern

• Null Object Pattern

• Visitor Pattern